Mongo field A greater than field B

Question

i\'m trying a simple query in Mongo which in MySQL would look like this.

select * from emails where bounceCount > sentCount;

So far I ha

Answer 1

Everyone seems to mention $where without really knowing that it is:

• slow
• insecure (evaled)
• JavaScript, not MongoDB internals
• And, on versions prior to 2.4, single threaded and global locked

Another method which would be a lot better for about 99% of cases is to use the aggregation framework:

db.col.aggregate([
    {$project: {ab: {$cmp: ['$bounceCount','$sentCount']}}},
    {$match: {ab:{$gt:0}}}
])